Please help if you want brianleist :}

Using the quadratic formula find the zeros of the given polynomial -5x^2+3x-11

The larger of two number is 4 less than twice the smaller number. the sum is 41. find the numbers

Sarah took the advertising department from her company on a round trip to meet with a potential client. including sarah a total of 11 people took the trip. she was able to purchase coach tickets for $280 and first class tickets for $1280. she used her total budget for airfare for the trip, which was $6080. how many first class tickets did she buy? how many coach tickets did she buy?